This report shares synthesised evidence on the mechanisms of youth mental health interventions, examines the gaps and opportunities for research, and shares insights from young people with lived experience of mental health problems. It identifies what the knowns and unknowns about how interventions for youth anxiety and depression work. It also includes recommendations for future research to fill the gaps and better inform policy and funding decisions. 

Looking at psychological, pharmacological, digital, lifestyle, social and creative interventions, the report highlights the way in which these interventions reduce symptoms. It identifies four major challenges:

1. weak mechanistic evidence and theory-practice gaps 
2. prevention research overlooks mechanistic risk factors
3. lack of research in low- and middle-income countries and diverse contexts 
4. limited lived experience and real-world relevance. 

The report concludes that to improve youth mental health outcomes, research must move beyond symptom reduction to understand how interventions work. This means testing mechanisms, tailoring interventions to diverse contexts and embedding lived experience.

Key recommendations

• Fund studies that test mechanisms using theory-driven designs.
• Prioritise prevention research targeting risk factors.
• Invest in culturally adapted interventions for low and middle-income countries. 
• Embed lived experience in all stages of research.
• Support underexplored areas like lifestyle, social, and creative interventions.